The involvement of the renin–angiotensin system (RAS) in the pathophysiology of coronavirus disease 2019 (COVID-19) is commonly discussed, because angiotensin-converting enzyme 2 (ACE2) is a functional receptor of SARS-CoV-2, and at the same time, a counter-balance for ACE in the RAS [1]. Here, ACE2 is linked to COVID-19.